Abstract:

The flow structure in ipsilateral vertical slot fishway is researched by changing the relative width of vertical slot (0.05, 0.10, 0.15, 0.30) and bottom slope 10% in a fishway model. Visual display and data analysis are adopted in the research. Through the simulation, the flow velocity distribution along water depth, the frictional distribution and attenuation of maximum flow velocity in mainstream area, as well as the turbulence kinetic energy distribution in the presence of different relative slot width and different flow velocity are obtained. Results reveal that when vertical slot width b₀/B=0.15 and bottom slope is 10%, flow pattern favorable for fish migration could be formed in the pool: the range of transverse diffusion of flow in mainstream area is moderate, the maximum flow velocity in the mainstream area attenuates uniformly along the way, and the backflow area is symmetrical with small flow velocity.

Key words: there-dimensional numerical simulation, ipsilateral vertical slot fishway, flow velocity distribution, Reynolds stress model, relative width of vertical slot